The crushing machines with traditional jaws exploit the principle of the breaking of the material that is being compressed between two jaws, of which one is fixed and the other mobile, the mobile jaw being operated by an eccentric power-operated shaft that acts on the upper side and by an articulation of a connecting rod that acts on the lower side, in the crusher called "a simple toggle", or the hinged mobile jaw being linked to the frame in the upper part and operated by an eccentric power-operated shaft through a double articulation connecting rod, in the crusher called a "double toggle". As is known, the traditional crushing machines have a correction system for the size of the material in exit which is awkward to use, being composed of a series of thicknesses inserted or removed between the connecting rod and the casing when the machine is standstill, with consequent laboriousness and known that in such machines the use of the safety device against blocks of uncrushable material is remarkably unsuitable and wasteful, this device being composed of the well known connecting rod or other breakable component that permits the mobile jaw to space itself from the fixed one beyond the correction/value, in order to eliminate the uncrushable material without giving rise to further and more serious damages to the machine. Since the security system is based on the breaking of a component, the relative reset involves an non-functional machine for many hours, for the replacement of the component and a notable cost for the material and labour.
U.S. Pat. No. 3,099,406 (H. A. P. KAUTZ) discloses an Ore Crusher having two opposed reciprocating jaws (10-21). The jaws being hinged upwards in the entry mouth and the reciprocation being operated backwards in their exit mouth; in which there is a release cylinder (C-3) to allow accidental enlargement.
This solution does not allow adjusting the exit mouth opening, but only safety against overpressure of a larger block not crushed. Furthermore oscillation being on their basis, does not supply an efficient and progressive crushing.
EP-A-0433500 (J. ALTIMAYER) discloses as the previously described IT-A-61977 B/90, a Rock crusher using a fixed jaw (1) and a reciprocable Jaw (16), said reciprocable jaw being eccentrically reciprocated in its upwards eccentric hinging (in the entry mouth). The reciprocable jaw having downwards and on its back a safety cylinder (double acting hydraulic ram 50) to allow opening of the exit mouth when excess of crushing pressure happens in the exit mouth.
In this solution the security cylinder (50) has a strongly limited allowable excursion because of the rigid connection ends of the cylinder (56-54).
In this solution spring clearance recovering device is provided (30-36).
GB-A-648443 (K. GAULDIE) discloses a two opposed Jaw crusher, having a fixed jaw and an hydraulically operated reciprocable jaw (12).
The hydraulic reciprocation being made by a cylinder (14) having both functions of reciprocation and of overpressure yielding.
The connection being made by simply pushing stem head in sliding contact with a vertical back surface on the basis (exit mouth opening) of the reciprocable jaw. Said mobile jaw being free hinged in upper side entry mouth opening.
This solution having a recovery clearance device (18-17a) as the previous one.
DE-B-1164211 (MASCHINENFABROK KOOPPEREN & Co. K. G.) discloses crusher structured as the previous one.
U.S. Pat. No. 4,749,132 (T. HAGIWARA) discloses: a crusher as per EP-A-0433500 with the difference to have an intermediate security pillar-bit or push-bit ("pivot" in the following description of this invention), and the stem of the cylinder being slidable in axial guide (3).
The push-bit being freely articulated in opposite ends by "rotula" connection.
This rotula connection being a unilateral rotary coupling.
DE-B-1237414 (KLOKENER-HUMBOLDT-DEUTZ AG.), discloses a crusher having both jaws freely hinged in entry mouth, the reciprocation being not made in their hinging.
The push-bar device being on one side and the yielding cylinder being on the other side on the other opposite jaw.
The cylinder articulation ends are made by pin-hinging that can cause easy breakage of the pins because of movement impressed to the respective jaws (5).
U.S. Pat. No. 2,982,481 (R. G. OSBORNE) discloses a crusher having a fixed jaw and an upside eccentrically hinged jaw, having in the back exit end a safety push-bar connection (183) that discharges in a very complicated way the excess of effort for exit overpressure to a very complicated mechanism, unable to allow wide regulation of the exit mouth opening, even if it uses a flag media (132) with two opposed security push-pars (115-137), in particular because these two opposed push-bars are not well articulated at their ends. The respective yielding safety hydraulic device (146, 149) does not provide adjustment of the exit opening of the jaws.
Patent Abstracts of Japan Vol. 1, no.137 (M-046) 11-Nov. 1977 Kokai No.52-78157 disclose: a crusher having a similar flag-push-bar couple security device on one side and security cylinder on the other.
Considering the data above, the drawbacks of the traditional crushing machines are evident, especially if utilized in crushing with the aim of recycling materials arising from demolitions, inasmuch as it is not possible to alter, with ease and continuity, the size of the material in exit during the functioning of said equipment and it is not possible to rapidly reset the machine once the security system has intervened
The aim of the present invention is precisely that of highlighting the aforementioned drawbacks and to define a crushing machine characterized by the possibility of varying with continuity, the size of the material in exit, during the normal functioning of the apparatus, and characterized by the fact that the security system against uncrushable material blocks is immediately able to be reset after the intervention.
More specifically, the device that allows the adjustment of the distance between the fixed and mobile jaws can assume different relative configurations, all characterized by the use of oleo-dynamic cylinders that act, depending on the solutions illustrated below, on the fixed jaw, on the mobile jaw, on the well known connecting rod or on one of the connecting rods in case of mills with double toggle.
In all the solutions that will be illustrated, the security function against uncrushable material blocks is entrusted to the oleo-hydraulic cylinders, connected to a circuit with one or more valves of maximum pressure that allows the discharge of the oil contained in the cylinders in case the pressure corresponding to the established maximum is exceeded, allowing the opening of one of the jaws and the consequent exit of the uncrushable block.
In what follows five preferential realizations are described that take as reference, the typological constructive scheme of a simple connecting rod crusher, for reasons of simplicity in the description. The same preferential realizations can make reference to the typological constructive scheme of the double toggle crusher, without changing the functional mode of the crusher operation.
According to a preferential realization of the present invention, the cylinders that carry out the double function of regulation of the distance between the jaws, determining the size of the blocks, are connected by means of rotary bilateral couplings, that are spherical articulations (rotula articulation), respectively to the mobile jaw and to the body of the machine. In this way, said cylinders, besides performing the two functions of correction and safety mentioned above, also replace the well known connecting rod, (traditionally, in the conventional crusher, to perform the safety function against uncrushable material blocks), whose breakage is pre-established. A normal oleo-hydraulic distributor allows the regulation of the opening of the jaws, while one or more valves of maximum pressure, duly calibrated, and of appropriate size, allow the rapid opening of the jaws to eliminate the block of uncrushable material, once the effort that is being used to generate itself for the presence of said block between the jaws, allows the calibration pressure of the valves in the cylinders, to be overcome. The rotary couplings between oleo-hydraulic cylinders and mobile jaw and between the said cylinders and body may be of a unilateral type, as in the case of two cylindrical surfaces, one concave, and the other convex, with more or less the same radius, or two spherical surface segments, being in this case necessary to prearrange a known tensioning system of the movable jaw towards the body, of the pulling and spring type or oleo-hydraulic cylinder connected to an oleo-pneumatic accumulator. In case the rotary couplings are of the bilateral type, the function of the tensioning may be carried out from the said oleo-hydraulic cylinders connected from the side of the stem with an oleo-pneumatic accumulator.
According to this invention, the oleo-hydraulic correction and safety cylinders do not act directly on the mobile jaw, as in the solution described above, but on the well known push connecting rod linked to the mobile jaw through an intermediate flag, the latter being hinged to the upper part of the isolated dihedral from the passing surfaces of the said cylinders and the well known connecting rod, or on the underside depending on the movements that one wishes to allow at the extremity of the flag, where the rotary couplings of the well known connecting rod and the cylinders converge. The evident advantage of this solution, (mechanically more complex with respect to the preceding), consists in being able to utilize a conventional type connecting rod with their own rotary couplings known and experimented in the technique, and to entrust to the cylinders only the opening adjusting and safety functions, without soliciting the rotary couplings of the same cylinders with continuos movements, these couplings having a very modest relative motion only in the correction case of the distance between the jaws or of the entering into function of the safety device against uncrushable material blocks, but not during the normal functioning, at numerous cycles per second, with less consequent wear and functioning reliability. Another advantage of this solution is in the sizing of the oleo-hydraulic cylinders that, if they lie on the surface not coinciding with the surface of the well known connecting rod, forming the two planes into a dihedral angle, may be expedited with less effort than if the case were coplanar to the well known connecting rod, depending on the amplitude of the above mentioned dihedral angle. In this case the effort coming from the well known connecting rod would discharge itself in part directly on the frame by means of the intermediate flag guide, being-able to utilize cylinders of smaller bore or make them work at a lower pressure, with repercussions on the cost or on the reliability of oleo-hydraulic components. Finally with this solution, when the surface of the well known push connecting rod and that of the cylinders almost coincide, it is possible to maintain, for the end part of the movable jaw, the same optimal trajectory that has been defined in the kinematics project site of the machine, also varying the opening of the jaws a great deal and therefore the size of the shattered material in exit.
In the solution described above, the rotary (rotula) couplings of cylinders and of the connecting-bits may be of unilateral or bilateral type, according to known technical solutions, necessitating the first type of tensioning system in the opposite direction of binding to hold everything mounted, the said operative tensioning system may also function as a system of recovering mechanical clearance due to the wearing of materials, the said system being composed of one or more oleo-hydraulic cylinders connected to an oleo-pneumatic the coupling clearances.